The artistic director of the Bolshoi ballet Sergei Filin on Wednesday dramatically confronted the former dancer accused of plotting to blind him with acid.

The artistic director of the Bolshoi ballet Sergei Filin on Wednesday dramatically confronted the former dancer accused of plotting to blind him with acid, rejecting allegations of an affair with a top young ballerina.

Filin, who nearly lost his sight in an acid attack early this year, took to the witness stand in the trial of former Bolshoi soloist Pavel Dmitrichenko who is charged with planning the assault.

In a stunningly frank testimony, Filin denied favouring ballerinas based on any "intimate relations" and said he cannot forgive anyone behind the attack.

"I don't forgive anyone for what happened," he said.

The testimony exposed yet more of the intrigue and plotting behind the scenes of the Bolshoi, whose reputation as one of the world's great ballet theatres was dealt a heavy blow by the attack.

Appearing in a dark suit with a high collar and dark eye glasses, Filin seemed calm and insisted on standing before the judge despite doctors' orders to avoid stress.

He denied that he had any conflicts with Dmitrichenko but admitted he had been warned before the attack that the dancer was seeking information to damage his reputation.

He described Dmitrichenko as an emotional young man and said he had been informed the soloist is trying to gather incriminating information about his love life and money affairs.

"As for intimate relations, I have a wonderful family, three children... The accusation that dancers passed through my bed is not as offensive to me as it is to the ballerinas that allegedly had affairs with me."

"It is a lie," he said.

'My wife does not dance like Smirnova'

The night he was attacked, Filin had been in the company of leading soloist Olga Smirnova, seen by many critics as the company's biggest new star and who enjoyed huge success on the Bolshoi's tour to London this summer

But Filin said Smirnova rose through the ranks because of her talent. He denied she was romantically involved with him and insisted he treated all ballerinas with equal fairness.

"My wife -- with whom I have intimate relations for 10 years -- does not dance like Olga Smirnova," he explained. Filin's wife Maria Prorvich dances in the corps de ballet.

Dmitrichenko, who was known for dancing dark characters like Ivan the Terrible, is said to have been frustrated by the lack of promotion under Filin for himself and his then girlfriend Anzhelina Vorontsova.

Also on trial are ex-convict Yury Zarutsky who is accused of carrying out the attack, while Andrei Lipatov is accused of driving the assailant to the scene.

Filin denied knowing the two alleged accomplices in the crime. All three men are held under arrest and appeared in the cage for defendants in the stuffy courtroom jam-packed with reporters.

Underscoring Filin's still unstable condition, the judge offered to take breaks in the proceedings, while a doctor was present in the courtroom to observe his well-being.

"He has been told to avoid stress," Filin's lawyer Natalia Zhukova told AFP before the hearing, but "will tell the court everything that is necessary".

"That is Filin's decision," she added.

Filin, 43, once a star and famously dashing dancer at the legendary theatre, in 2011 became the artistic director of the ballet troupe.

He was cornered in January this year near his house by an assailant who threw acid on his face, causing grave injuries to eyes and skin.

The attack shocked the ballet world in Russia and abroad, while Filin was forced to undergo months of treatment and operations in Germany. The scandal eventually caused the dismissal of Bolshoi director Anatoly Iksanov.

If convicted, the three accused could be sentenced to up to 12 years in prison.

Dmitrichenko, who has been under pre-trial arrest since March, last week pleaded not guilty, saying he had never intended for Filin to be injured so severely.

Investigators allege that Dmitrichenko had a conflict with Filin over distribution of roles and planned to have the former ballet star permanently maimed.